Design and Construction of a Sensitive Electronic Control System for the Injection of Fast Transient Pulses into a Current Measurement System

摘要

This paper discusses the design and construction of a test station used in research to improve the high frequency response of optical current transformers (OCT's). The system comprises of a short circuit high current busbar loop, two 5 kVA current transformers (CT's), a standard CT and the current transformer under test. The standard CT is used to measure the main power supply current injected into the loop by driving the first 5 kVA CT via an 8 kVA Variac from the main electric network, whilst the second 5 kVA CT is used to inject high frequency current signals into the system. Apart from this electronic control to be in very close contact with the busbar, high voltage experiments are also done in the same laboratory, including corona discharge and other interferences that made it essential to employ electrostatic and electromagnetic screening of the electronic circuits. During this project, many special techniques have been developed and used to achieve this effective screening.